갈릴리안 광학계를 사용한 IM/DD 광무선통신 시스템에서 830[nm] 광파장에 대한 전송거리 제한 해석

홍권의(Kwon-Eui Hong),고성원(Sung-Won Ko),조정환(Jung-Whan Cho) 한국조명·전기설비학회 2011 조명·전기설비학회논문지 Vol.25 No.11

In terrestrial wireless optical communication links, atmospheric effects including turbulence, absorption and scattering have significant impact on the system performance. Based on the analysis of transmission in atmospheric channel concerning 830[nm] wavelength diode laser beam, performance of free space optical (FSO) link utilizing Galilean optics as a laser beam transmitting and receving optics, PIN photodiode as a detecting device. In this paper we designed optical link equation for received optical power and we analyze the atmospheric effects on the signal to noise ratio (SNR) and bit error rate (BER) of an terrestrial FSO system. We show that the possible communication distance for BER=10_-9 in proposed adverse atmospheric conditions.

교란대기 지상 광무선 통신에서 변조방식에 따른 패킷 오류율 비교

홍권의(Kwon-Eui Hong) 한국통신학회 2014 韓國通信學會論文誌 Vol.39 No.12(네트워크)

지상 광무선 통신에서 대기의 교란 및 대기 입자에 의한 광의 감쇄가 있을 때, 대기교란의 강도 및 가시도가 수신 광 강도에 미치는 영향을 해석하였다. 광신호는 On-Off Keying(OOK), Pulse Position Modulation(PPM) 및 Digital Pulse Interval Modulation(DPIM)의 방식으로 변조하였다. 교란대기 하에서 각 변조방식에 대해 광 전송거리에 따른 광수신 전력을 계산하고 이를 이용하여 전송거리에 따른 패킷 오류율(packet error rate: PER)을 계산하였다. 광신호를 전송하기 위한 광원의 파장은 850nm, 1310nm 및 1550nm을 선택하였다. 대기는 약 교란 상태로 가정하여 대기 굴절률 구조상수 Cn2?10-14m-2/3, 대기의 가시도 V=2km로 하였다. 약교란 대기 상태에서 세가지 변조방식 중 DPIM 방식이 우수하며, 광 신호의 전송을 위한 파장으로는 1550nm가 PER 성능이 우수함을 알 수 있었다. In the terrestrial optical wireless communication(OWC), the performance is affected by atmospheric turbulence and particles in the air. The received signal power loss mainly is caused by turbulence and scattering. To minimize the adverse atmospheric effects, the OWC used optical signal modulation, such as OOK, PPM and DPIM. In this paper, the packet error rate(PER) was analyzed above three modulation methods to ground optical link in atmospheric turbulence, scattering and link distance. The OWC system used three wavelengths which are 850nm, 1310nm and 1550nm. I assumed the atmospheric turbulence intensity is weak, so the refractive index is Cn2?10-14m-2/3 and the visibility is 2km. The numerical results shown that the L-DPIM scheme and the wavelength 1550nm are better than other modulation methods and wavelengths.

카세그레인 광학계를 사용한 광무선통신 시스템에서 550[nm], 850[nm] 및 1550[nm]의 광 파장에 대한 안개 및 포인팅 에러의 영양에 대안 해석

홍권의(Kwon-Eui Hong) 한국조명·전기설비학회 2008 조명·전기설비학회논문지 Vol.22 No.12

안개 및 대기의 교란이 광무선 통신에 주는 영향을 해석하기 위해 가시광선영역의 LD(laser dieode) 및 적외선 영역의 LD 사용하고, 카세그레인 광학계를 이용하여 광을 송수신하게 하였으며, 광 소신소자로는 APD(avalanch photo diode)를 사용함을 가정하여 대기 중의 안개의 정도에 따른 가시도 및 교란의 세기를 나타내는 굴절륜 구조 상수에 따른 광 수선 전력, 잡음 전력을 고려한 SNR(signal to noise ratio)을 계산해 보고 각각의 통신 상태에서 BER(bit error rate)이 10<SUP>-9</SUP>이 가능한 통신 거리를 알아보았다. Atmospheric effects on laser beam propagation can be broken down into two categories: attenuation of the laser power and fluctuation of laser power due to laser beam defomation. Attenuation consists of scattering of the laser light photons by the fog. Laser beam deformation occurs because of small-scale dynamic changes in the index of refraction of the atmosphere. This causes pointing error. In order to analyse these effect on optical wireless communication system, in this paper uses cassegrain optics as a transmitting and receiving telescope, APD as a detecting device and LD as a light source. The signal modulating and demodulating method is a IM/DD. I show the effects of fog and pointing error and calculate the possible communication distance for BER is 10<SUP>-9</SUP>.

경근 이론을 중심으로 관찰한 매선요법의 이해;안면부를 중심으로

홍권의,Hong, Kwon-Eui 대한침구의학회 2008 대한침구의학회지 Vol.25 No.3

Objects : This study is desinged in order to clinical applications of the new acupucture method : embedding therapy. Conclusions : 1. Emdedding therapy apply to many disease through the effect of physical stimulation and chemical stimulation. 2. Facial muscles belong to one or more meridian muscle. 3. Emdedding therapy can be used in facial disease through meridian muscle system.

Alkaline phosphatase와 N-telopeptide의 검사(檢査) 측정(測定)을 통(通)한 임상적(臨床的) 고찰(考察)

홍권의,이현,이병렬,Hong, Kwon-Eui,Lee, Hyun,Lee, Byung-Ryul 대한침구의학회 2001 대한침구의학회지 Vol.18 No.5

Objective : The purpose of this study was to inspect the effect of Oriental medicacl treatment with following up NTx and absorbing rate of bone in degenerative osteoarthritis. Methods : To obtain this result, we examinated 52 case of parents who visit Dept. of Acupuncture and Moxibustion Oriental Medical Hospital. Taejon University. We observe their age, sex, symptoms and change of NTx and ALP. Results : As a result of this examination, we detected the fact that it's difficult to decending NTx, but we are convinced that Oriental medicine has a good effect clinically. Conclusion : We take very useful result from this study, and want to be put this knowledge to practical use on treating Osteoporosis think the study like this must be go on continuously.

배독요법을 통한 아토피환자 2례에 대한 임싱적 고찰

홍권의,Hong, Kwon-Eui 대한약침학회 2007 Journal of pharmacopuncture Vol.10 No.2

Objectives : This study is desinged in order to evaluate the Poison extraction method for the Atopic dermatitis. Methods : The authors observed the two cases of Atopic dermatitis patients who previously used steroid-based ointment. for treating the Poison Extraction Method. Conclusions : 1. In case 1, the patient with mild case of Atopic dermatitis in face is treated with the Poison extraction method. Rash symptoms intensed for first few days. As sweating appeared in the local area from the seventh day, all the symptoms was disappeared rapidly. No recurrence was found. 2. In case 2, the patient with severe case of Atopic dermatitis in whole body is treated with the Poison extraction method. The symptoms intensed after two months and all the symptoms of itchiness, rash, scaly letter dissapeared in the third and fourth months. No recurrence was found. 3. In both cases of mild and severe cases of Atopic dermatitis. all the symptoms were disappeared and no recurrence was found with the Poison Extraction Method.

교란대기가 ASK 지상 광통신(光通信)시스템에 미치는 영향

홍권의,김준환,정진호,김영권,Hong, Kwon-Eui,Kim, June-Hwan,Jung, Jin-Ho,Kim, Yung-Kwon 한국전기전자학회 1997 전기전자학회논문지 Vol.1 No.1

Since the wireless optical communications system transmits informations through the atmosphere, it is subject to many effects of the constituent materials of atmosphere. The turbulence effect always exists in both clear and cloudy days. It causes a beam wandering, breathing, and scintillation. These disadvantageous phenomena degrade the performance of an optical communications system. In this paper, I designed a refractive index measuring system and subcarrier ASK optical communications system. Through this system I measured refractive index in May and in August. From these measurements, the minimum value of the refractive index in these period was about ${\approx}10^{-15}[m^{-2/3}]$ at night time and the maximum value was about ${\approx}10^{-12}[m^{-2/3}]$ at day time. The refractive index structure parameter. BER(bit error rate), and the burst length were measured simultaneously in these measurements. the theoretically predicted BER and the measured values showed a good agreement. 본 논문은 레이저를 이용한 지상 광통신에 교란대기가 미치는 영향을 해석하기 위한 것으로, 대기의 교란은 밝은 날이나 흐린 날에도 존재한다. 대기 교란으로 인하여 전파해 가는 광선은 빔의 방황, breathing, 신틸레이션이 발생하며 이는 광통신 시스템 성능의 저하를 가져온다. 이를 해석하기 위하여 대기굴절률 구조상수 측정 시스템 및 레이저 다이오드를 이용한 지상 광통신 시스템을 설계하였고. 이를 이용하여 대기의 굴절률 구조상수에 따른 지상 광통신 시스템의 비트 오류률을 이론적으로 유도하고 실험하였으며, 연집 오류와의 관계를 실험을 통해 구하였다.

약침제제(藥鍼製劑)의 시술 후 안전성 및 유효성에 대한 설문 조사 분석

홍권의,Hong, Kwon-Eui 대한약침학회 2010 Journal of pharmacopuncture Vol.13 No.3

This study was done in order to present clinical trial method for safety and efficacy of Pharmacopuncture. The results were summarized as follow: Objective : The purpose of this study is to verify about safety and effectiveness of pharmacopuncture. Methods : We use questionnaire created by expert group. Survey was conducted to target clinicians who using pharmacopuncture more then 5 years. Results & Conclusion : Pharmacopuncture is effective. and that is widely used in the musculoskeletal diseases. but treatment method has not been organized to objectivity. Some pharmacopuncture causes specific symptoms, but no serious side effects. Generally, pharmacopuncture is effective and safety.

세 채널 Rib형 결합기를 이용한 광 편파기 설계

홍권의,이원석,호광춘,Hong, Kwon-Eui,Lee, Won-Seock,Ho, Kwang-Chun 한국전기전자학회 2003 전기전자학회논문지 Vol.7 No.1

유효 유전체 해석법에 기초한 정확한 모드 전송선로 이론이 세 채널 rib형 광 방향성 결합기의 편파된 빔 분리를 분석하기 위하여 소개되고 발전되었다. 또한, 본 논문에서 제안한 방법의 타당성을 보이기 위하여 상용 소프트웨어인 BeamPROP를 이용하여 그 결과들을 비교 검토하였다. 분석결과, 하나의 채널을 통하여 rib형 광 방향성 결합기에 입사된 혼성(hybrid) 모드들은 임의의 편파거리를 진행한 후에 상, 하 채널을 통하여 잘 분리됨을 알 수 있었다. A rigorous modal transmission-line theory (MTLT) based on effective dielectric method (EDM) is introduced and developed to analyze the polarization beam-splitting of optical rib-type directional coupler with three guiding layers. Furthermore, to confirm the validity of approach proposed in this paper, we compare our results with those ones of BeamPROP, which is a commercial software package used widely. Consequently, the numerical results reveal that the hybrid modes incident into a guiding channel of rib-type coupler are split well through upper and lower guiding channels in a polarization length.

삼음교(三陰交)(Sp6) 전침자극(電針刺戟)이 fMRI상 뇌활성변화(腦活性變化)에 미치는 영향(影響)

홍권의,이병렬,이현,임윤경,김연진,Hong, Kwon-eui,Lee, Byung-ryul,Lee, Hyun,Yim, Yun-kyoung,Kim, Yun-jin 대한침구의학회 2003 대한침구의학회지 Vol.20 No.3

Objective : Recently, many studies have showed the evidences of the effect of the acupunture treatment through scientific methods. One of these methods is functional MRI. We performed electro-acupunture on Sp6 and observed the changes of brain activation using fMRI. Methods : To see the effect of electro-acupunture stimulation on Sp6, the experiment was carried out on 12 healthy volunteers, using the gradient echo sequence with the 3.0T whole-body MRI system(ISOL). After the needle insertion on right Sp6, 2Hz of electric stimulation was given for 30 seconds, repeated five times, with 30 seconds' intervals. The Image analysis including motion correction, talairach transformation, and smoothing was done with SPM99. Results : 1. Group averaged brain activation induced by bilateral eletro-acupunture stimulation on Sp6 activates Brodman Area 3, 7, 13. 2. Group averaged brain deactivation induced by bilateral eletro-acupunture stimulation on Sp6 activates Brodman Area 6, 38, 47. 3. Group averaged brain activation induced by unilateral(right side) eletro-acupunture stimulation on Sp6 activates Brodman Area 5, 6, 13, 17, 18, 19, 31, 38, 40 ptoms, back pain(32.5%) was the 4. Group averaged brain deactivation induced by unilateral(right side) eletro-acupunture stimulation on Sp6 activates Brodman Area 3, 4, 18, 21, 36, 38, 39. 5. Brain region activated by motor stimulation activates Brodman Area 3, 4, 6, 18, 19.